In recent years, awareness of safety while driving vehicles has improved, and a variety of technologies for facilitating the driving operations or the like and thereby improving safety have been proposed and put into practice. Parking assistance devices have been implemented in which, e.g., locations that are difficult for the driver to see are imaged by a camera mounted on the vehicle and are displayed on a monitor device within the vehicle cabin. A device for monitoring the rear of a vehicle, in which an actual image of the rear of a self vehicle captured by a camera is shown on a display, is disclosed in Patent Document 1, the reference for which is given below. This device switches the displayed image from an actual image to a converted image as the distance from the current position of the self vehicle to the target position decreases. The converted images are also sequentially switched from converted images having a low viewpoint to converted images having a high viewpoint.    [Patent Document 1] Japanese Laid-open Patent Application No. 2003-267171 (e.g., the 9th through 20th paragraphs, the 34th paragraph, FIG. 4, FIG. 6, and FIG. 7)